Teeth whitening is mainly used to treat stained teeth, such as tetracycline teeth, fluoride teeth, etc. The general methods of teeth whitening are cold light whitening, laser whitening, porcelain veneers, and full crown restoration. Nowadays, laser whitening is more commonly used. This whitening method has good aesthetic effect in addition. Compared with porcelain veneers and full crown restorations, there is no need to grind away the tooth tissue during the process of teeth whitening, which is in line with the treatment principle of preserving as much healthy tooth tissue as possible. Before doing teeth whitening, you must have a thorough oral examination, treat some oral diseases, such as dental caries, periodontitis, etc. For patients with very bad oral hygiene, scaling should be performed. You should also apply gum protector around the gums, and then use 30% hydrogen peroxide as a tooth whitening agent and apply it on top of the teeth. After that, the teeth are lighted with the whitening handle of the laser so that the whitening effect can be achieved. Compared with cold light whitening, laser whitening has the characteristics of fast and effective. The light exposure time is short and the whitening effect can last for a long time. After the laser whitening, you can use the home whitening paste to achieve better whitening effect.